1. Field of the Invention
This invention relates generally to the field of mechanical material moving apparatus, and also to the field of wine making, and more particularly to a system for pumping wine musts and pomaces. The predominant current usage of the invention is for a pump for pumping wine pomace to a pressing process after the free run wine is removed.
2. Description of the Related Art
Wine making is a lengthy process involving many critical steps. For purposes of the present invention, the wine making process can be summarized by the following method. First, the wine grapes are crushed into a must containing both grape juice and solids. The must is then placed into a fermentation tank in which it is fermented for approximately eight to fourteen days. The free run wine is then removed from the fermentation tank leaving a wet mixture of wine pomace (the grape solids in addition to a small amount of leftover free run wine), which is often then transferred to presses to extract additional wine.
There are three known methods for transferring the wine pomace from the fermentation tank to another process, such as a pressing process. One method is to attach an auger to the bottom of the fermentation tank. When the auger rotates, the pomace is fed into a transport bin, a winery piping system, a belt conveyor, or the like, in order to transport the pomace to the next process. The primary drawback of using augers to transport wine pomace is the expense. Typically, each auger can cost between $250,000 and $500,000, thereby creating large overhead costs for the winery.
A “dig” method can also be used to remove wine pomace from the fermentation tank. In the dig method, a worker enters the fermentation tank to shovel the wine pomace through a hole in the tank and into a transport bin. A concern with using the dig method is safety. The confined space and oxygen deprived environment within the fermentation tank presents a worker hazard. Also, the fermentation tanks are sometimes angled near the bottom and workers might slip and become injured. Also, in at least some jurisdictions it is required that a standby worker and a designated rescue person be on hand when a worker enters the fermentation tank. Therefore, a method which could accomplish the task without requiring a worker to enter the tank would reduce employee cost, as well.
Yet another method for removing the pomace is a sluicing method. In the sluicing method a portion of the free run wine is injected into the pomace to form a slurry of wine and pomace. The slurry is then pumped through winery piping or into transport bins. However, passing the wine slurry through a pump is undesirable because grape seeds are broken and skins are shredded. The broken seeds and skins can have an adverse effect on the appearance and/or taste of the wine.
One disadvantage when using methods such as those described above to transport wine must and pomace is that the wine product is excessively exposed to atmospheric air, which is higher in oxygen concentration than the air within and surrounding the fermentation tank(s). The exposure to increased oxygen levels during transport can have detrimental effects on the wine quality.
What is needed, therefore, is a system for moving wine musts and pomaces that is both cost effective and safe to wine makers and employees, and further that will not adversely affect the wine musts and pomaces during the pumping process, such as by increasing the wine product's exposure to oxygen during transport.